Electronic structure of monolayer Cu, Ag and Au structures

Abstract

Within the framework of the density functional theory, the features of the electronic structure of copper, silver and gold monolayers are investigated. Changes in the electronic states of slabs are investigated depending on the number of monolayers and the concentration of defects. The tendencies in the formation of the total density of electronic states curve during the transformation from a monolayer to a bulk sample for copper and gold are of a similar character. It has been established that the shape of the total density of electronic states curve of gold slabs with a thickness of 1–3 monolayers is mainly determined by the components of the d-states associated with the z axis. In the case of three monolayers, the shape of the total density of electronic states curve is specified by the d-states of the atoms of the outer layers. Point defects, which are smaller than the atomic size and are observed in STM images of gold monolayers, are determined by the peculiarities of atomic ordering. The presence of topological neighbors of the atoms of the metals under study lead to the broadening of the band and the formation of the lower part of the valence band. The loss of a larger number of atoms in the slab leads to a significant shift of the main maximum of the d-states of the metal towards lower binding energies, while a smaller number of atomic defects in a monolayer lead to the splitting of the initial features.